"Gerry" <[EMAIL PROTECTED]> made an utterance to the drakelist gang ---------------------------------------------------------------------- ... final adjustment is made by "centering" the oscillator between the two sideband filters.
Exactly. The filters are not perfect. They have slight variations in both center frequency and more importantly on slope. When you get down to it, manufacturing two filters that are an exact match to each other in all characteristics but opposite sidebands was a pretty tall order. Therefore the final adjustment is done by ear. In the end, you may not even need to use a frequency counter except to troubleshoot. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Garey Barrell Sent: Monday, October 30, 2006 9:39 AM To: Frank Cc: [email protected] Subject: Re: [drakelist] Calibration 9 MHZ TR4-C Garey Barrell <[EMAIL PROTECTED]> made an utterance to the drakelist gang ---------------------------------------------------------------------- Frank - Easiest is to just make a small loop of wire at the input cable to the counter and hold it near the CAR OSC tube in the right rear corner of the TR-4C. Set it to 9.0000 MHz, but the final adjustment is made by "centering" the oscillator between the two sideband filters, i.e., adjusting the trimmer carefully while switching back and forth with the sideband switch. You should be able to find a point where the hissing noise is the same "pitch" when switching back and forth. 73, Garey - K4OAH Chicago Drake 2-B, B & C Line Service Supplement CDs <www.k4oah.com> Frank wrote: > Frank <[EMAIL PROTECTED]> made an utterance to the drakelist gang > ---------------------------------------------------------------------- > Hallo > Please , on TR4-C Where is the point for measured test > with digital_count for 9 MHZ calibration (c130) . > Tnx Frank > > > ---------------------------------------------------------------------- Submissions: [email protected] Unsubscribe: [EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost: [EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net ---------------------------------------------------------------------- ---------------------------------------------------------------------- Submissions: [email protected] Unsubscribe: [EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost: [EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net ----------------------------------------------------------------------
